package com.lyun.common;

import org.springframework.data.geo.Point;

public class DistanceUtils {

    private final static double EARTH_RADIUS = 6378.137;

    private static double rad(double d) {
        return d * Math.PI / 180.0;
    }

    public static double getDistance(double lat1, double lng1, double lat2, double lng2) {
        double radLat1 = rad(lat1);
        double radLat2 = rad(lat2);
        double a = radLat1 - radLat2;
        double b = rad(lng1) - rad(lng2);
        double s = 2 * Math.asin(Math.sqrt(Math.pow(Math.sin(a / 2), 2) + Math.cos(radLat1) * Math.cos(radLat2) * Math.pow(Math.sin(b / 2), 2)));
        s = s * EARTH_RADIUS;

        s = (s * 10000) / 10;
        return s;
    }

    public static double getDistance(Point point, Point toPoint) {
        //经度
        double longitude1 = rad(point.getX());
        double longitude2 = rad(toPoint.getX());
        double a = longitude1 - longitude2;

        double b = rad(point.getY()) - rad(toPoint.getY());
        double s = 2 * Math.asin(Math.sqrt(Math.pow(Math.sin(a / 2), 2) + Math.cos(longitude1) * Math.cos(longitude2) * Math.pow(Math.sin(b / 2), 2)));
        s = s * EARTH_RADIUS;

        s = (s * 10000) / 10;
        return s;
    }
}
